Under laboratory conditions, the activity of two entomopathogenic nematodes, Heterorhabditis bacteriophora (HP88) and Steinernema carpocapsae (AT4), as well as their compatibility with two common insecticide formulations (lambada cyhalothrin and flubendiamide) and one insect growth regulator (lufenuron), were evaluated against Spodoptera frugiperda. The nematode IJs were subjected to the LC 50 and LC 25 of insecticides, and the viability of infective juveniles (IJs) was measured before being tested against Galleria mellonella larvae to determine IJs pathogenicity. Also, the mixtures were evaluated against the 4 th instar larvae of S. frugiperda to select one mixture can serve in integrated pest management (IPM) in agro-ecosystems. Results showed that H. bacteriophora strain (HP88) was more efficient with higher pathogenicity and virulence against 4 th larvae of S. frugiperda (LC 50 = 48.67±0.34IJs/ml -1 ) than S. carpocapsae (AT4) (LC 50 = 65.88± 3.04). flubendiamidee was the most toxic insecticide (LC 50 = 3.26±0.52) followed by Lambada cyhalothrin (4.23±0.8PPM). Lufenuron was the least toxic one (5.67±1.53PPM). Both EPN H. bacteriophora (HP88) and S. carpocapsae viability was not affected by any of tested insecticides (LC 25 and LC 50 ), while lambada cyhalothrin reduced S. carpocapsae pathogenicity with LC 50 concentration. Lufenuron at the rate LC50 and Lc25, not affect H. bacteriophora and S. carpocapsae pathogenicity. All tested insecticides with the two doses were harmless according to IOBC test. All mixtures of insecticides with the two EPN strains were synergistic effect against 4 th larvae of S frugiperda except lufeuron with LC 25 was antagonist. It was explored how these nematode insecticide combinations could be used in maize pest management.
Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is an invasive alien species especially infested tomato crops. It invaded Egypt in 2009 and many plantations. It's difficult to control due to the limitation of insecticides, therefore, the susceptibility of T. absoluta to three indigenous isolates of entomopathogenic nematodes in Egypt, i. e. Heterorhabditis bacteriophora (EKB20), Steinernema sp. (B32) and Heterorhabiditis sp. (Kasassien isolate) were determined in the laboratory, greenhouse, and field experimental compared with emamectin benzoate insecticide. Leaf bioassays were carried out to evaluate the affinity of nematode isolates to reach the larvae and affect them at the galleries. The efficacy of the three nematode species after foliar application to potted tomato plants was evaluated under laboratory conditions. High larval mortality (70.6-94%) and low pupae mortality (<25%) were determined. In the leaf bioassay tests, a high level of larval infestation (75.4-88.6%) indicated the nematode's ability to kill the larvae within the galleries compared with 100% mortality of emamectin benzoate with the recommended dose. In the pot experiments treatment plants with nematode caused a reduction in insect infestation by 87-94% compared with 96% in the treatment of emamectin benzoate. The results of the field experiment showed the efficiency of entomopathogenic nematodes for reducing infestation with T. absoluta with 70 to 90 % reduction % compared with more than 95% with emamectin benzoate. The results suggested that EPN are considered promising biocontrol agents, if correctly applied and released in integrated control schemes against the tomato leaf miners T. absoluta.
The bioassay of some Silver nanoparticles AgNP synthesized botanically against Meloidogyne javanica J2. was conducted. All materials were prepared and evaluated at the concentrations of 100, 50, 25 and 12.5µl/50 ml of nematode suspension. Mortalities% of M. javanica J2 were recorded after 96 hrs. The obtained data explained the increasing of Meloidogyne javanica J2 with the increasing of the material concentrations. AgNP prepared by oleander extract gave mortality of M. javanica J2 ranged between 37.1and 93.25% with the low and high concentrations. The LC50 was 15.31µl/50 ml. Nanoparticles of silver by chamomile cause 34.30 and 91.33% mortality of 2 nd nematode juvenile with the low and high concentrations. The LC50 was 18.72µl/50 ml. The Ag NP synthesized by thyme cause 14.3 and 91.0% mortality of M. javanica J2 with the low and high concentrations, respectively. LC50 was 37.71µl/50 ml. The formulation of AgNP by ginger gave mortality of 52.0 and 92.0%. LC50 was 11.11. Silver nanoparticles formulated by jojoba surpassed other botanical formulation causing 59.55 and 95.84% mortality with the low and high concentrations, respectively and the LC50 was 10.24µl/50ml. Chemical preparation of AgNP cause mortality of 40.8 and 82.0% at low and high concentrations. The LC50 was 18.88. The effectiveness of chitosan at the low molecular weight at the concentrations of 100, 50, 25 and 12.5µl/50ml was tested revealing that at low and high concentrations the mortality ranged between 72.34 and 96.8 %, respectively. The estimated LC50 was 5.16µl/50 ml. These results explain the superiority of chitosan over other materials.
The main objective of this research is to recognize the rodent species prevailing under Minia region, Egypt conditions. The current study revealed the presence of three main species of rodents living in two animal farms (Salah El-Deen village and El-Minia district), El-Minia Governorate. These species of rodent were: Rattus rattus frugivorous; Rattus norvegicus and Mus musculus. The ectoparasites associated with these rodents were: two insects i.e., the louse, Polyplax spinulosa; the Flea, Pullex irritans as well as six mite species i.e., Ornithonyssus bacoti; Glycyphagus sp.; Myobia murismusculi; Dermanssus gallinae; Liponyssoides sanguineus and Cheyletiella parasitivorax. The mite species, O. bacoti; Glycyphagus sp. and C. parasitovorax were recorded on the bodies of R. r. frugivorous and R. norvegicus, but these species of mites were recorded from the body of the house mouse, M. musculus. The two mite species M. murismusculi and D. gallinae were recorded in association with the three surveyed rodent species. The fleas were more common with R. r. frugivorous and M. musculus, but completely disappeared with R. norvegicus. The louse, P. spinulosa was recorded on R. r. frugivorous and M. musculus and completely missed on R. norvegicus. In Shosha animal farm (Samalote district), only two rodent species were recorded (R. r. frugivorus and R. norvegicus), and the mite species accompanied with both rodent species were O. bacoti; Glycyphagus sp.; M. murismusculi and C. parasitivorax. While the lice, P. spinulosa were found only on the body of R. r. frugivorous and completely disappeared on R. norvegicus.
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